Battery packs are presently used to provide electrical power to numerous devices, including tools, vehicles, laptop and tablet computers, and mobile phones. In many applications, the physical space required for the battery pack or packs is a crucial design consideration that affects many aspects of a product, including physical size and shape and performance. For example, the available operational time of a portable electronic device and the physical range of an electronic vehicle are both directly affected by the volume of space available to the battery pack and the efficiency of usage of the available volume. In many battery pack applications, it is desirable to safely and efficiently maximize usage of battery pack volume, for example to add electrical capacity to the product, reduce the battery pack size, or to allow for more efficient cooling of a battery pack.
A common type of battery is a rechargeable battery with a lithium-based chemistry—for example, a lithium-ion or a lithium-polymer battery. Lithium-ion and lithium-polymer batteries typically contain a cathode current collector; a cathode comprised of an active material, a separator, an anode current collector; and an anode comprised of an active material. The cathode can comprise a cathode coating, and the anode can comprise an anode coating. The cathode, separator, and anode assembly is typically assembled in a cylindrical or prismatic “jelly roll” configuration within a battery casing, with conducting anode and cathode conducting terminals, arranged to protrude into its corresponding active material and allow for a point of electrical connection external the battery casing. A battery casing of existing batteries may typically be neutral, but also may be at cathode (positive) potential or anode (negative) potential.
Existing battery packs typically use a bus bar or another similar means including one or more conductor separate from the battery cells, which is usually welded to terminals of a battery cell to form an interconnection system. The bus bar and similar interconnection systems consume space within a battery pack that could be used for other purposes if a more efficient battery interconnect system were to be implemented.